That's actually the only positive thing I've taken from the whole "HP is joining the 21st century" announcement. I'm not a fan of Harry Potter, but I'm a huge fan of authors breaking the traditional publishing rules when it comes to ebooks.

As to the OP's original question, the answer is NO, for what I consider to be an obvious reason: Pottermore has no business interest whatsoever in pushing Amazon to abandon MOBI and adopting EPUB, so they won't.
AS to DRM, my understanding is that Pottermore is opting for a social DRM scheme, in which the buyer's credit card number would be digitally watermarked unto each copy sold. Will that work to protect Ms. Rowling's IP rights as well as regular DRM? Color me skeptical, but we will find out in a few months.

Wow, exciting news! This is something I've longed for since I started buying eBooks. Amazon's selection of eBooks is without doubt among the best (if not the best) on the market, but I've never been a fan about their decision using the mobi format. Even though they offer reading apps to all major smartphone and computer OSes, Kindle is the only e-reader that have native support for mobi as far as I know.

I love my Kindle, but lately I've ended up buying ePub eBooks from other stores, removed the DRM, converted to mobi and finally transferred them to my Kindle. If Amazon decides to sell future eBooks in ePub format I'll be their most loyal customer ever

However, if they decide to go for the ePub standard, do you think Amazon will offer all books in ePub, or just selected ones?

Yes, I probably should have said a few rather than the only one. Yet I think that the support for ePub is much better than mobi among both pure e-readers and eBook reading apps on Android Market for instance.

I just hope that ePub will be the standard format for eBooks, just as MP3 is more or less the standard within the music industry.

Yes, I probably should have said a few rather than the only one. Yet I think that the support for ePub is much better than mobi among both pure e-readers and eBook reading apps on Android Market for instance.

I just hope that ePub will be the standard format for eBooks, just as MP3 is more or less the standard within the music industry.

If no-DRM is a requirement then no need for ADE as well. Amazon could simply sell non-DRM mobi through their site. I don't think that format is important in this case as HP books have simple formatting. The real benefit could come from accepting DRM-less publishing.

Amazon cannot sell the books through their site. Pottermore is the only place that is going to sell the books.

The method of purchase is what Google Checkout provides. I think Amazon could provide something similar via Amazon Marketplace, but the sale at least seems like it needs to be initiated from Pottermore. Target used to be hooked up through Amazon, for example (add to cart on Target.com, checkout ultimately goes through Amazon).

In terms of format, I believe it is important, as it finally gets Amazon/Kindle on the ePUB bandwagon. For one thing, other books have more complex formatting and ePUB could produce better results. And for another, this brings us one step closer to breaking the device/bookstore lock in on the Kindle.

and tons of other public domain books are not only illustrated, but the illustrations are part of the reason these books are classics. The mobi file format doesn't reproduce these books very well.

I've never noticed a difference. Mobi seems to do images quite well enough for the portable reading devices for which these books appear to be intended.

From a practical point of view, most books today will be formatted to look pretty much the same in either format, Kindle still being the most popular reader, so I doubt anyone would go to the trouble of publishing distinctly different versions for epub and mobi. Publishers tend create with the common, and easily inter-convertable, features in mind.

As an owner of both an epub and a mobi reader, however, if you happen to have any examples of epubs that highlight something epub can do over mobi, that is of any practical value to the reader , I would be curious to see it. Otherwise the differences seem to be academic, or limited to a tiny niche of the market at best.

I know, that's why I added "more or less" In any case, I believe that it's about time the eBook industry comes together and agrees on one specific format. It would've made a lot of things so much easier.

The reason I would like to see Amazon decide for the ePub format, is that so many other major eBook stores have. But Amazon has, especially with its Kindle, obtained a very solid position within the eBook market. Thus, it's now Amazon against the rest in terms of formats used. If you therefore choose Amazon's mobi format, you'll most likely be stuck with Amazon for a long time if you want to be able to read all your previously bought books. And while this might be just what Amazon wants, it's not what I, as a user, want.

Many other eBook stores now uses Adobe Digital Editions for handling the DRM. More and more eBook readers support this standard as well. As a result, more freedom and access to your books on more devices and applications. I'm therefore now buying all my books using other eBook stores. I'm not saying I'm correct and that my opinion is the best, it's just my thoughts on the situation. And history tells us that forcing users to one format/platform is not how you keep users staying with you. Take a look at the music industry, it's been through many of the same dilemmas.

Just like a music store selling MP3, an eBook store can set its own price and restrictions, but still offer a book in standard format.

Many other eBook stores now uses Adobe Digital Editions for handling the DRM.

Many smaller book stores use Adept DRM.
Major stores with their own associated ereaders do not. Amazon don't, Apple don't, B&N don't and Kobo only do when selling to non-Kobo devices, they use their own DRM for their own devices. Any (English-speaking) major player who has the option of using their own DRM rather than paying Adobe has taken than option.

terms of format, I believe it is important, as it finally gets Amazon/Kindle on the ePUB bandwagon. For one thing, other books have more complex formatting and ePUB could produce better results. And for another, this brings us one step closer to breaking the device/bookstore lock in on the Kindle.

What's the business case for Pottermore pushing Amazon to switch formats? I know its technically cool and all , but Pottermore is not going to do this unless they are receiving some financial advantage for doing this.
I'm genuinely curious. Why would Pottermore pick this fight, rather than simply offering the books in mobi as well as epub formats on their site-the way manybooks, feedbooks and Project GT do?

What's the business case for Pottermore pushing Amazon to switch formats? I know its technically cool and all , but Pottermore is not going to do this unless they are receiving some financial advantage for doing this.
I'm genuinely curious. Why would Pottermore pick this fight, rather than simply offering the books in mobi as well as epub formats on their site-the way manybooks, feedbooks and Project GT do?

A very good question.

The business reason would be that they only have to produce one book format instead of two. Beside that, what's to stop another player from coming along and demanding books in their format.

Amazon may pay them to release in .mobi format, and that would settle that. OTOH, Rowling herself owns the digital rights and (presumably) makes the final decision on anything. I don't know how easy it is to bribe the richest woman in the world!